1. Field of the Invention
This invention relates to the lot processing technology and more particularly to a power supply system, power supply method and lot processing method.
2. Description of the Related Art
At present, the power consumption used in a semiconductor manufacturing factory is large. Therefore, it is desired to suppress the power consumption from the viewpoint of a cost reduction and protection of the environment.
Conventionally, as a power saving method, a method for setting a processing unit into an energy saving mode when the standby time of the processing unit becomes longer than a preset time is known (for example, refer to Jpn. Pat. Appln. KOKAI Publication No. 2004-200485). However, once the processing unit is set in the power saving state, it takes a long time as the start-up time required for restoring the processing unit to an operative state in order to process the next lot. Therefore, the process cannot be instantly started even if the lot arrives at the processing unit, and throughput is lowered. At present, it is difficult to attain power saving operation without lowering the throughput.